Why did Eliezer tell Rivkah's family about Avraham's wealth?
Rashi (in Pasuk 36): It was to encourage them to allow Rivkah to marry him. He showed them the document testifying that Avraham gave everything that he owned to Yitzchak. 1
Rashbam and Seforno: To flatter them - in that many people hoped that Yitzchak would marry their daughters, but Avraham refused them all, because he was only interested in his family in Charan.
Ha'amek Davar: He detailed his wealth, to avoid them suspecting that they Hashem's B'rachah was that Avraham should be happy with his lot, but that he has nothing to bequeath to Yitzchak.
What is "va'Yigdal"?
Malbim: He became important (like "Asher Gidelo ha'Melech" (Esther 5:11). 1
Ha'amek Davar: It is a good reputation.
Malbim: He explained how HaSh-m blessed Avraham in three matters in which people succeed (and Haman would later boast about) - importance, wealth and children (see the next verse, "Sarah gave birth..." (24:36)).
Why are "va'Avadim u'Shefachos" written Chaser (without a Yud and a Vav)?
Ha'amek Davar: This teaches that Avraham did not conduct with them so much like slaves.
